Manufacturing atomically-precise functional nanoarchitectures with tailored physics at well-defined device interfaces is a frontier in bottom-up nanomaterial [1,2] and condensed matter design [3]. A long-standing challenge in the field is the integration of functional elements in proof-of-concept devices. One strategy to alleviate the cumbersome device integration of single-layered molecular systems, is to achieve increasing control over vertical supramolecular heterojunctions and multilayers, so as to transition from ‘on-surface’, to ‘out-of-surface’ surface science protocols. [more]

A mechanistic understanding of the dissociation of O₂ molecules adsorbed on metal surfaces is crucial not only for the precise control of oxidation reactions but also for the development of various heterogeneous oxidation catalysts. [more]

Polarons [1] are quasiparticles that form in ionic lattices due to the interaction of excess charges with lattice distortions. This leads to a spatial confinement of the charge and appearance of many novel phenomena. In past decades, polarons turned out to play an important role in electrical transport, optical properties, organic electronics, catalysis, or in exotic materials properties such as colossal magnetoresistance or high-Tc superconductivity. [more]

Ultrathin metal films on atomically flat semiconductor substrates have been of great interest to investigate physical properties of two-dimensional (2D) metals. Indium-adsorbed Si(111) surfaces are one of the most explored metal/semiconductor systems. [more]

Perovskite surfaces attract attention in the catalysis community due to these materials’ promising chemical properties, good ability to separate electron-hole pairs in light harvesting, and the presence of ferroelectricity in many perovskites. While perovskites possess a unique set of interesting bulk properties, their surfaces are much less understood; the main open questions are their structural stability and associated chemical reactivity and catalytic selectivity. [more]

The first topic of this talk is focused on the atomic-scale processes of dissociative adsorption and spillover of hydrogen on the single atom alloy catalyst (SAAC) Pd/Cu(111) [1]. The hydrogen spillover on the Cu(111) surface from the Pd site was successfully observed in real-time using infrared reflection absorption spectroscopy (IRAS) at 80 K. The observed chemical shifts of Pd 3d5/2 in X-ray photoelectron spectra (XPS) indicate that H2 is dissociated and adsorbed at the Pd site initially. [more]

Exploration of essential photophysics at the level of individual molecules and atoms requires highly specialized optical spectroscopies that work at the very limit of instrument sensitivity or have to use plasmonic nanostructures - in order to overcome the fundamental resolution limits achievable with visible and infrared light. [more]

We investigate second-harmonic generation (SHG) light from a Pt surface in air under terahertz (THz) pulse irradiation. THz pulse-modulated SHG intensity shows a clear time profile of the THz field. [more]

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Using low-temperature scanning tunneling microscopy and occasionally synchrotron radiation methods we investigate molecules at surfaces. The experiments along with model calculations reveal molecular spin states and electron transport properties as well as intermolecular interactions. [more]

Liquid-Solid interfaces are the primary region where molecules interact through molecular motion and chemical reactions. However, it is challenging to gain insight into how interactions between the surface and solution modify molecular behavior. A powerful tool for evaluating these phenomena and molecular properties is in-situ surface-sensitive vibrational spectroscopy, such as surface-enhanced Raman scattering (SERS) induced by plasmonic materials.[1] [more]

We aim to control the symmetry of molecular spin structures on solid surfaces and design a two-dimensional (2D) organic quantum bit network with exceptional quantum spin properties. To achieve this, we have employed transition metal atoms and organic molecules as materials. Over the past two decades, we have investigated surface spin structures using scanning tunneling microscopy and spectroscopy (STM/STS), as well as spin-polarized STM/STS, all conducted in ultrahigh vacuum (UHV) at cryogenic temperatures, in combination with density functional theory (DFT) calculations [1-4]. [more]